Acute lymphocytic leukemia (ALL), also called acute lymphoblastic leukemia, is a cancer of the bone marrow and lymph system. The bone marrow produces early blood-forming cells, called stem cells, which grow and mature into the three blood cell types: white blood cells, which fight infection; red blood cells, which carry oxygen to tissue; and platelets, which help blood to clot. ALL is characterized by uncontrolled production of immature lymphocytes (white blood cells), of which there are two types: B and T cells. These immature lymphocytes never mature enough to perform their specific function of fighting infection. In addition, these rapidly dividing cells crowd out and suppress the formation of other important blood cells, such as red blood cells, platelets and other white blood cells. Treatment for ALL is typically aggressive therapy, including high-dose therapy and stem cell transplantation. ALL is the most common type of leukemia in children. Some early research suggested that electromagnetic exposure, like living next to high-voltage power lines, was a possible risk factor for developing childhood leukemia. However, more recent studies have failed to document an increased incidence of childhood ALL in individuals living near power lines. Until now, the association between power lines and cancer has remained unclear.
Researchers from England and Wales recently conducted another large study to evaluate data regarding a possible relationship between living close to high-voltage power lines and the incidence of childhood leukemia. Researchers studied the records of over 29,000 children between the ages of 0 and 14 years with cancer, including 9,700 with leukemia. They found that children who lived within 200 meters of high-voltage power lines had a 70 percent increased incidence of leukemia compared to individuals who lived more than 600 meters away. There was also an observed 23-percent increased incidence in those living between 200 and 600 meters. A link between proximity to power lines and cancer incidence appears limited to leukemia-there was no increased risk between living close to power lines and the incidence of other cancers. The increased risk of developing leukemia would add an estimated five additional cases to the current 400 to 420 annual childhood cases in England and Wales .
The researchers concluded that results from this large study indicate that living within 200 meters of high-voltage power lines increases the risk of developing childhood leukemia. However, they had no scientific explanation for this observed relationship as there are no animal models that explain this phenomenon.
Reference: Draper G, Vincent T, Kroll ME, et al. Childhood cancer in relation to distance from high voltage power lines in England and Wales: a case-control study. British Medical Journal. 2005;330;1290-1294